Water heater

Abstract

A water heater in which water is heated by microwave energy. A tank which holds water is separated by a horizontal partition into a relatively small upper chamber and a larger lower chamber. Incoming cold water enters the upper chamber and is heated by a magnetron which produces microwave energy. A transfer conduit accommodates the flow of hot water from the upper chamber to the lower chamber when water is discharged from the lower chamber through an outlet pipe. When the water in the lower chamber cools, a pump returns it to the upper chamber for reheating. The pump and magnetron are controlled by thermostats which maintain the water in the upper and lower chambers at different temperature levels.

Having thus described the invention, I claim: 
     
       1. A water heater comprising: a first tank for holding water;   an inlet to said first tank for supplying incoming cold water thereto;   means for applying microwave energy to the water in said first tank to thereby heat the water therein when the temperature of the water in said first tank is below a preselected temperature level;   a second tank adjacent said first tank for holding water;   an outlet for said second tank for discharging heater water therefrom;   conduit means providing communication between said first and second tanks, thereby accommodating flow of hot water from said first tank to said second tank when heated water is discharged from the second tank and incoming cold water enters the first tank through said inlet; and   pump means for pumping water from said second tank to said first tank when the temperature of the water in said second tank is below a predetermined temperature level, said preselected level being greater than said predetermined level to maintain the first tank at a higher temperature than the second tank.   
     
     
       2. The invention of claim 1, wherein said first tank is located above said second tank. 
     
     
       3. The invention of claim 1, including: means for sensing the temperature of the water in said first tank;   means for energizing said applying means when the water temperature sensed by said sensing means is below said preselected level; and   means for deenergizing said applying means when the water temperature sensed by said sensing means is above said preselected level.   
     
     
       4. The invention of claim 3, including: second sensing means for sensing the temperature of the water in said second tank;   means for effecting an active condition of said pump means when the temperature sensed by said second sensing means is below said predetermined level; and   means for effecting an inactive condition of said pump means when the temperature sensed by said second sensing means is above said predetermined level.   
     
     
       5. The invention of claim 1, including: means for sensing the temperature of the water in said second tank at a plurality of discrete locations; and   means for activating said pump means to pump water from said second tank to said first tank when the temperature sensed at all of said discrete locations is below said predetermined level.   
     
     
       6. The invention of claim 1, wherein said second tank has a larger capacity than said first tank. 
     
     
       7. A water heater comprising: an enclosed tank for holding water; a partition in said tank dividing same into an upper chamber and a lower chamber located generally below said upper chamber;   a cold water inlet conduit for said tank communicating with said upper chamber to supply incoming cold water thereto;   means for applying microwave energy to the water in said upper chamber to thereby heat the water therein;   a hot water outlet conduit for said tank communicating with said lower chamber to discharge heated water therefrom;   a transfer conduit extending through said partition to provide communication between said upper and lower chambers, whereby to permit flow of hot water from said upper chamber to said lower chamber when heated water is discharged from the lower chamber through said hot water outlet conduit and incoming cold water enters the upper chamber through said cold water inlet conduit; and   pump means for pumping water from said lower chamber to said upper chamber when the temperature of the water in said lower chamber is below a predetermined level.   
     
     
       8. The invention of claim 7, including means for deenergizing said applying means when the temperature of the water in said upper chamber exceeds a preselected level. 
     
     
       9. The invention of claim 7, including: means for energizing said pump means when the temperature of the water in said lower chamber is below said predetermined level; and   means for deenergizing said pump means when the temperature of the water in said lower chamber is above said predetermined level.   
     
     
       10. The invention of claim 7, including: first sensing means for sensing the temperature of the water in said upper chamber;   means for deenergizing said applying means when the temperature sensed by said first sensing means is above a preselected temperature level;   second sensing means for sensing the temperature of the water in said lower chamber;   said pump means having an active condition and an inactive condition and being operable in the active condition to pump water from said lower chamber to said upper chamber;   means for effecting the active condition of said pump means when the temperature sensed by said second sensing means is below said predetermined temperature level; and   means for effecting the inactive condition of said pump means when the temperature sensed by said second sensing means is above said predetermined temperature level.   
     
     
       11. The invention of claim 7, including: means for sensing the temperature of the water in said lower chamber at a plurality of discrete locations; and   means for activating said pump means to pump water from said lower chamber to said upper chamber when the temperature sensed at all of said discrete locations is below said predetermined level.   
     
     
       12. The invention of claim 7, wherein said lower chamber has a greater capacity than said upper chamber. 
     
     
       13. A water heating appliance comprising: first and second tanks for holding water, said second tank having a larger capacity than said first tank;   a cold water inlet to said first tank for supplying incoming cold water thereto;   means for applying electromagnetic microwave energy to the water in said first tank to heat the water therein when the water temperature in said first tank is below a predetermined level;   a hot water outlet for said second tank for discharging heated water therefrom;   pump means having an active condition and an inactive condition and being operable in the active condition to pump water from said second tank to said first tank;   means for effecting the active condition of said pump means when the temperature of the water in said second tank is below a preselected level less than said predetermined level and for effecting the inactive condition of said pump means when the temperature of the water in said second tank is above said preselected level, whereby heated water in said second tank which cools to a temperature below said preselected level is returned to said first tank for reheating; and   conduit means providing communication between said first and second tanks, thereby accommodating flow of hot water from said first tank to said second tank when water enters the first tank through said inlet or through pumping acting by said pump means.   
     
     
       14. The invention of claim 13, wherein said first and second tanks are located in a common enclosure with said first tank disposed above said second tank. 
     
     
       15. The invention of claim 13, including means for deenergizing said applying means when the temperature in said first tank exceeds a predetermined level greater than said preselected level. 
     
     
       16. The invention of claim 13 wherein said effecting means includes: means for sensing the temperature of the water in said second tank;   means for effecting the active condition of said pump means when the temperature sensed by said sensing means is below said preselected level; and   means for effecting the inactive condition of said pump means when the temperature sensed by said sensing means is above said preselected level.   
     
     
       17. The invention of claim 13, wherein said effecting means includes: means for sensing the temperature of the water in said second tank at a plurality of discrete locations therein;   means for effecting the active condition of said pump means when the temperature sensed at all of said discrete locations is below said preselected level; and   means for effecting the inactive condition of said pump means when the temperature sensed at any of said discrete locations is above said preselected level.